This study aims at evaluating perceived service quality in Zanjan University of Medical Sciences (ZUMS). This study was cross-sectional and authors surveyed educational services at ZUMS. Through stratified random sampling, 384 students were selected and an adapted SERVQUAL instrument was used for data collection. Data analysis was performed by using SPSS 11.5. The results indicated that there were the negative mean score of quality gap in all dimensions of the service quality. Overall services quality mean was (-1.6 ± 0.78). The highest and lowest differences of mean scores between students' expectations and perceptions were in the responsiveness and (-1.83 ± 1.01) and reliability (-1.33 ± 0.79) dimensions respectively. Paired t-test showed the significant statistical differences between students' expectations and perceptions (? < 0.001) in all dimensions of the service quality. Thus, improvement actions are felt in all domains of the educational service quality; Students rated the responsiveness as the most important dimension of service quality in ZUMS.